不平衡电网下风电并网变流器的滑模电流控制

doi:10.16183/j.cnki.jsjtu.2018.09.009

上海交通大学学报（自然版） ›› 2018, Vol. 52 ›› Issue (9): 1065-1071.doi: 10.16183/j.cnki.jsjtu.2018.09.009

不平衡电网下风电并网变流器的滑模电流控制

韩刚，蔡旭

上海交通大学风力发电研究中心，上海 200240

通讯作者: 蔡旭，男，教授，博士生导师，电话(Tel.): 021-34207001；E-mail: xucai@sjtu.edu.cn.
作者简介:韩刚(1985-)，男，江苏省徐州市人，博士生，主要研究方向为风电接入及变流器的优化控制技术.
基金资助:
国家自然科学基金项目(51677117)，台达环境与教育基金会项目(DREM2016005)

Sliding-Mode Control of Current for Wind Power Grid-Connected Converter Under Unbalanced Grid Voltage

HAN Gang,CAI Xu

Wind Power Research Center, Shanghai Jiao Tong University, Shanghai 200240, China

摘要/Abstract

摘要： 为了增强对不平衡电网的适应能力，提出一种适用于LCL型并网变流器的滑模电流控制策略.建立了电流内环及电压外环的滑模控制方程，采用指数趋近率的设计方法改善滑模动态品质与系统抖振，根据扩展瞬时功率理论计算参考电流指令，在实现三相并网电流呈正弦波形变化的同时，消除了并网有功功率和扩展无功功率的2倍频波动.同时，搭建了基于RT-LAB软件的硬件在环实验控制平台，通过对比实验验证了所提滑模控制算法的正确性，及其在动态响应速度和抗参数扰动方面的优越性.

关键词: 并网变流器, 不平衡电压, 滑模电流控制, 硬件在环, 参数鲁棒性

Abstract: In order to strengthen the ability in adopting unbalanced grid voltage, a sliding-mode control strategy of current for grid-connected converter with an LCL filter was proposed, and the sliding-mode governing equations of inner current loop and outer voltage loop were established, respectively. Dynamic quality and chattering effect of the designed sliding-mode controller were improved by using exponential rate control method. The referenced current was generated based on extended instantaneous power theory, and the objective of three-phase sinusoidal current was achieved while the second frequency fluctuation in both active and extended reactive power were eliminated. Finally, hardware-in-loop experimental platform based on RT-LAB was built. Results of comparative experiment demonstrated the correctness of proposed algorithm, as well as the excellent properties in dynamic response speed and parameter robustness.

Key words: grid-connected converter, unbalanced voltage, sliding-mode current control, hardware-in-loop, parameter robustness

中图分类号:

TM 464

韩刚，蔡旭. 不平衡电网下风电并网变流器的滑模电流控制[J]. 上海交通大学学报（自然版）, 2018, 52(9): 1065-1071.

HAN Gang,CAI Xu. Sliding-Mode Control of Current for Wind Power Grid-Connected Converter Under Unbalanced Grid Voltage[J]. Journal of Shanghai Jiaotong University, 2018, 52(9): 1065-1071.

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